Technical Abstract:
Permittivity and electrical conductivity are complex numbers that vary with frequency. Spectra for a range of frequencies provide more information than can be derived from data at a single frequency. The objectives of this study are to develop tools for spectra measurements on a variety of soils, and to examine spectra variations as a function of water repellency. We discuss spectra results from packed soil samples for two sizes of coaxial sample holders, and development of a probe to measure thermal and electrical properties for undisturbed samples.